By cheating on his wife, who later succumbed to cancer, and by fathering a child out of wedlock and denying that fact on national TV, Edwards became one of America’s most-despised politicians. The conventional wisdom was that he was a goner if a jury ever decided his fate after his indictment last year for allegedly conspiring to raise almost $1 million in illegal campaign donations to support his mistress during the 2008 presidential race.

But during the trial, Edwards’s defense has managed to divert attention from the two-time presidential candidate’s moral failings and developed several plays that could convince the jury to acquit him.

Proving that Edwards knew about the scheme to support his mistress Rielle Hunter may be easy compared to the other big hurdle prosecutors face: proving that the former senator knew that having a couple of donors support and hide his mistress was illegal.

Fans of courtroom TV dramas know that ignorance of the law usually isn’t much of a defense. But for these charges, it is. Because campaign finance law can be highly technical (and probably because the members of Congress who wrote the law could readily imagine themselves running into such troubles), the criminal charges require knowingly and willfully violating the law.

Getting inside Edwards’s head on this point is no easy task—particularly since he never took the stand in his own defense.

Prosecutors contend Edwards’s efforts to conceal the affair, the child and the payments is evidence of his guilty mind. But that web of lies is just as easily explained by the ex-senator’s worries about his wife’s reaction and by his attempts to preserve what was left of his reputation as by some fear of legal repercussions.

What prosecutors are left with is the notion that Edwards, a talented lawyer and presidential candidate twice over, must have known what he was doing was illegal. The problem with that claim is that many reputable campaign finance lawyers, including at least two former Federal Election Commission chairmen, say the kinds of payments at issue in Edwards’s case are not subject to donation limits or required to be reported. The prosecution fought valiantly to keep those kinds of opinions from the jury—precisely because they could torpedo the government’s case.

To be sure, there’s a gaping hole for the defense here. Young claims the ex-senator told him several times that he’d checked with campaign finance lawyers who said the arrangement was legal and didn’t violate election laws.

“The government’s going to take the position that that was a lie,” lead prosecutor David Harbach said in court Wednesday.

Indeed, while Young’s comments about how Edwards responded to the legal concerns have been brought up again and again by Edwards’s defense, they’ve never presented any evidence that the former senator really did ask someone for legal advice on whether the payments needed to be reported. If the defense had good evidence of that, Edwards would probably have never been indicted in the first place.

But the burden of proof lies with the government—making the intent element perhaps the largest obstacle to an Edwards conviction.

The missing witnesses

Neither of the two donors who bankrolled Hunter—Fred Baron and Rachel “Bunny” Mellon—appeared in the courtroom. Baron, the finance chairman for Edwards’s 2008 campaign, died of cancer in October of that year. Mellon is 101 and wasn’t required to testify.

The role of Edwards’s wife Elizabeth was also central to the case. But she died of cancer in December 2010.

Other absences could raise more questions in the minds of the jury—and none more than that of Hunter, who might have added more than just drama for the assembled reporters.

Prosecutors introduced phone records suggesting that Edwards and Hunter spoke dozens of times while she was living in luxury on Baron’s dime. The clear implication was that Hunter told Edwards where she was and who was footing the bill for her first-class exile. But since she wasn’t called to the stand, the jury never heard that from her.

Another missing witness: Baron’s wife, Lisa Blue. Edwards adviser Jennifer Palmieri described to jurors an October 2007 meeting at an Iowa hotel where Edwards’s wife exploded in anger at Baron and Blue after learning they’d had been entertaining Hunter, including with air travel and by taking her shopping. Palmieri said Edwards was at the meeting and said little, but his presence indicated he knew something of the wealthy couple’s generosity to Hunter.

Blue presumably could have backed up Palmieri’s account, but prosecutors never called Blue to explain her version of what happened.

Jurors could conclude that the prosecution is deliberately not giving them the full story. And when juries don’t think they’ve gotten the warts-and-all truth from the government they often acquit, especially in white-collar cases with no obvious victim.

All this….. for that?

Edwards’s team has clearly embraced the time-honored defense tactic of putting the prosecution on trial—particularly when it comes to suggesting that the government has gone too far in making a federal case out of a situation of sexual infidelity.

Edwards’s lawyers may also be hoping that some of the intensely emotional moments in the trial left at least some jurors feeling like they were unwillingly intruding into a neighbor’s exceedingly unpleasant domestic spat. At one point the jury heard testimony about a confrontation between Edwards and his wife where staffers saw Elizabeth rip open her blouse, expose her breasts and scream, “You don’t see me any more” at her cheating husband.

Judge Catherine Eagles has told the jury that Edwards isn’t on trial for being a bad husband or for having an affair, but defense lawyers have stoked the overkill argument, pointing to tactics and investments of resources that could seem disproportionate to a campaign finance case. Defense attorney Alan Duncan noted that an FBI agent was “racing down the highway” with his siren on to try to spot Edwards getting off a private jet at a small North Carolina airport.

On Wednesday morning, defense lawyer Allison Van Laningham noted to the jury that the investigation of Edwards has spanned three-and-a-half years.

“Do you have any idea [about] the number of FBI agents that may have been assigned to the case?” she asked a defense expert. Eagles sustained a prosecution objection to the question, but the point was made.

And it’s not like the amount of money at issue here is huge compared to the sums raised in the 2008 election—and certainly not compared to the hundreds of millions sloshing around in the 2012 presidential race.

There’s been no mention in the courtroom that billionaire Sheldon Adelson and his wife, for example, spent $20 million dollars in recent months in a futile quest to help Newt Gingrich win the Republican presidential nomination. But jurors may already know that, or at least have the impression that the campaign finance system allows for vast sums of money to flow into the political system in which official limits are just speed bumps for candidates and donors.

In an era of presidential candidates appearing at Super PAC fundraisers where millions of dollars are solicited, jurors may find arguments over a mere $925,000 to be like trying to patch a small hole in the hull of a ship that has already sunk.

Young’s a liar

Andrew Young, the former Edwards aide who falsely posed as the father of Edwards’s out-of-wedlock child, is often billed as the prosecution’s star witness. If so, he’s not sparkling quite so brightly following his cross-examination and a parade of witheringly critical defense witnesses.

”If Andrew told me it was raining, I would go look out the window,” longtime Edwards adviser Harrison Hickman told the jury this week. He and others called Young dishonest and said he was prone to exaggerating his role in events.

The defense has also relentlessly raised the fact that much if not most of the money Young got from Mellon and Baron went to cover $1.6 million in construction costs on Young’s new home.

As a legal matter, the fact that Young may have been out to make money for himself doesn’t rule out the possibility that Edwards, Mellon and Baron conspired to break the election laws. But it hurts Young’s credibility by making him look more like an operator and less like a naif that Edwards took advantage of.

Another blow to Young’s standing: just before the defense rested Wednesday, prosecutors agreed to stipulate to the jury that Young considered selling a sex tape of Hunter and Edwards. Jurors were told the contemplated sale never happened, but the impression of shadiness may be hard for Young to shake.

A question of timing

The prosecution contends that the money was paid to cover-up an affair so it didn’t hurt Edwards’s presidential prospects. But money was paid long after he’d pulled the plug on his White House run, timing that doesn’t support the notion that the cash was linked to Edwards’s presidential campaign.

The defense has pointed to money that was still going to Hunter and the Youngs far into 2008.

Some aspects of the timing are clearly not good for Edwards. Due to a combination of Edwards’s bad luck and exceedingly bad judgment, Hunter’s pregnancy became obvious just as the 2008 presidential campaign was kicking into high gear. And as a result of the National Enquirer tracking her down in North Carolina in December 2007, the most intense phase of the effort Baron financed to hide her came just days before the lead-off Iowa caucus.

While the defense contends Edwards and his top aides already knew by then he wasn’t going to be the Democratic nominee for president, the fact that Hunter and Young took off for a cross-country trek in the weeks before Edwards dropped out on January 30, 2008 muddles the timing issue. Nonetheless, one of the defense’s central arguments to the jury will be that the money spigot wasn’t turned off when Edwards dropped out and in fact it flowed even faster as Edwards’s political fortunes declined.